Process of preparing vat dyestuffs of the pyranthrone series and new vat dyestuffs prepared thereby



Patented Dec. 10, 1935 UNITED S'i'iiifll.

PROCESS @F PREPARENG VAT OF THE PYRANTHBQNE SERKE AND NEW VAT DYESTUFFSPREEARED THEREBY Georg Kranzlein, Heinrich Vollniann, and WernerSchultheis, Frankfort-on-the-Main-Hcchst, Germany, assignors to GeneralAniline Works, Inc., New York, N. 2., a-corporation oi Belawere NoDrawing. Application April 4, 1932, Serial No. 603,201. in Germany April17, 1931 6 Claims. (Cl.'260-=-61) The present invention relates to aprocess of temperature, while well stirring. The melt which preparingvat dyestuffs of the pyranthrone is at first yellowish-red assumes aviolet coloraseries and to new vat dyestuffs prepared thereby, tion andfinally turns blue. After one hour the more particularly it relates tonew compounds of whole is decomposed with water and the orange- 5 thegeneral formula: brown crude product is purified by re-vatting it 0 orby treating it with hypochlorite. The yield of II purified dyestuffamounts to about 20 parts=50 X per cent of that of the theory. Thedyestufi' crystallizes from nitrobenzene in the form of reddish-yellowneedles; it dissolves in sulfuric acid to a blue solution, dyes cottonfrom a violetblue vat orange tints and behaves in every respect likepyranthrone.

I Y (2) 80 parts of pyrene are dissolved in 168 5 parts ofbenzoylchloride at water-bath tempera- -X ture. The solution is run atabout 130 C.-about I 150 (3., while stirring, into a melt of 1350 parts0 of aluminium chloride and 250 parts of sodium chloride. Thetemperature is raised, while well 20 sg fi two X S or the two Y S areSubstltuted stirring, to about 150 C.- about, 170 C. and oxygen We foundthat Vat dyestuffs of the is introduced until the color of the melt hasberanthrone series are obtainable by condensing come The whole 9 Wlthwater pyrene with an aromatic carboxylic acid derivaand further treatedas descnbed Example tive of the formula: There are obtained 80 parts ofpur1fied dyestuff which is identical with that obtainable accordingaryl-CO.R to Example 1.

(3) A solution of parts of pyrene in 350 parts ofm-chloro-benzoylchloride is run at about 130 G. into 400 parts ofaluminium potassium chloride in'the proportion of 1 mol. of AlzCls to 1in the presence of aluminium chloride while introof Ttlereuponpyrqlusite is .introduced ducing a dehydrogenizmg agent into thereaction while stlrring, in small portions until the color a lue whichis the case mixture. The yield oi the dyestuifs obtamable of the melt abecome b according to the said process on an average after 20-30minutes. The melt 1S worked up and amounts to 50450 Der cent of that ofthe theory the crude dyestuff is purified as described in the Yields ofsuch a high percentage were not to be plfeceding examples The dyestflffh Obtamed expected in View of the facts hitherto, known dissolves inconcentrated-sulfuric acid to a blue In carrying out the present processit is solution having a more greenish hue than that 40 vantageous to addto the melt of aluminium chloobtamed Wlth dyestufi of Example 1 f dyesride an admixture which facilitates the melting cotton from m Vat 3 5tmts' It process, such as an alkali halide or an excess of probably hasthe followmg constltutlon: the acid chloride or acid anhydride. Asdehydroo genizing agents there may be used gaseous oxygen, air or solidoxidizing agents such as heavy metal oxides or certain non-metal oxides.

The following examples serve to illustrate the 01 invention, but theyare not intended to limit it thereto, the parts being by weight: (1) Asolution of 20 parts of pyrene in 28.2 parts of benzoylchloride is runat about C.-about C. into a melt of 270 parts of aluminiumchloride and58 parts of sodium chloride, while stirring. The melt is rapidly heatedto II 55 about C. and oxygen is introduced at this 0 wherein Rrepresents halogen or the group -OCOaryl, the two aryls being identical,and 30 wherein the aryl group contains at least one unsubstitutedortho-position to the ketonic group,

needles and yields from a bluish-red vat clear orange tints of goodfastness properties. It probably has the following constitution:

, By using instead of para-toluyl-acid chloride meta-toluyl-acidchloride, a similar dyestuff is obtained.

(5) 20 parts of pyrene are introduced, while stirring, into a solutionof .30 parts of benzoic acid anhydride in 400 parts of sodium aluminiumchloride (NaCl-A12Cls) at about 120 C.-about 130 C. The reddish-violetmelt is'vigorously stirred, while introducing air, until'its color hasbecome clear blue. Thereupon, the melt is decomposed with water andthecrude dyestuif which has been precipitated is purified by revattingit. The dyestuff thus'obtained is identical with that obtainableaccording to Example 1.

(6) A solution of 20 parts of pyrene in 40 parts of a-naphthoylchlorideof about C. is introduced at about C.-about C., while stirring, into 500parts of sodium aluminium chloride and subsequently treated with air oroxygen as indicated in the preceding examples, until the color of themelt has become blue. The dyestuff thus obtainedrather diificultly formsa vat and yields on cotton brownish-orange tints.

(7) To a melt prepared from pyrene, benzoylchloride, aluminium chlorideand sodium chloride as described in Example 1, there are gradually addedat about C.-about C., while stirring, about 20 parts of voluminous ironoxide. The oxygen of iron oxide acts as a dehydrogenizing agent so thatthe melt rapidly assumes the blue color of the solution of pyranthrone.The product is worked up as described in Example 1.

We claim:

1. The process which comprises condensing pyrene with an aromaticcarboxylic acid derivative of the formula:

aryl-CO-R wherein R represents halogen or the group -O.CO.aryl, the twoaryls being of the benzene or naphthalene series and being identical,and wherein the aryl group contains at least one unsubstitutedortho-position to the ketonic group, in the presence of aluminiumchloride while introducing a dehydrogenizing agent into the reactionmixture.

2. The process which comprises condensing pyrene with benzoylchloride inthe presence of sodium aluminium chloride while introducing a 5dehydrogenizing agent into the reaction mixture.

3. The process which comprises adding a solution of pyrene inbenzoylchloride to a melt of sodium aluminium chloride, while stirring,at a temperature of about 110 C.about 120 0., heat- 10 ing the mixtureup to about 160 C. and introducing oxygen at this temperature, whileWell stirring, until the color of the melt has changed to blue.

4. As new products, the compounds of the 15 formula:

wherein the two Xs or the two "T5 are substituted 30 by methyl.

5. As a new product, the compound of the formula:

crystallizing from quinoline in the form of orangeyellow needles andyielding from a bluish-red vat clear orange'tints of good fastnessproperties. 50

6. As a new product, the compound of th formula:

I OH;

crystallizing from quinoline in the form of orangeyellow needles andyielding from a bluish-red vat clear orange tints of good fastnessproperties.

GEORG KRANZLEIN. HEINRICH VOLLMANN. WERNER SCI-IULTHEIS.

